OMP, the olfactory maker protein, is an abundant protein whose expression is restricted almost exclusively, to mature olfactory neurons. Since its discovery nearly 30 years ago, by the co-I, OMP has been used by many laboratories as the definitive identifier of mature olfactory neurons. The primary sequence of OMP is phylogenetically conserved across vertebrate species and is 55% identical from Xenopus to human. In addition, the organization and sequence of the OMP gene promoter is conserved in several mammals. Nevertheless, OMP has no homologs in the databases and, until recently, its function in olfactory sensory neurons has been elusive. The recent generation of OMP-null mice has provided clear in vivo and in vitro evidence for the involvement of OMP as a novel participant in the olfactory signal detection/transduction cascade. To study this at the protein structural level we propose to use NMR spectroscopy of isoptically labeled OMP to solve its structure and its dynamical properties. Knowledge of OMP's structure and dynamics will provide a structural context for characterization of its intrinsic functionality and that which is associated with its interaction(s) with other components of the olfactory signal detection/transduction cascade. Further, this study represents the first NMR structural solution for any protein involved in chemosensory transduction.